You installed VLC thinking it was a magic bullet. But without the exclusive HEVC codec, you are watching 4K movies in slow motion. By following this guide—installing the hardware decoder, tweaking the loop filters, and forcing video outputs—you transform VLC into a professional-grade HEVC player.
Install K-Lite Codec Pack Basic (uncheck all bundled tools except “VLC plugin”). During install, enable “HEVC (H.265) decoding via FFmpeg”.
sudo pacman -S vlc ffmpeg